RGD uses the Human Disease Ontology (DO, https://disease-ontology.org/) for disease curation across species. RGD automatically downloads each new release of the ontology on a monthly basis. Some additional terms which are required for RGD's curation purposes but are not currently covered in the official version of DO have been added. As corresponding terms are added to DO, these custom terms are retired and the DO terms substituted in existing annotations and subsequently used for curation.
A primary bacterial infectious disease that results_in infection, has_material_basis_in Borrelia burgdorferi, which is transmitted_by blacklegged tick (Ixodes scapularis) or transmitted_by western blacklegged tick (Ixodes pacificus). The infection has_symptom fever, has_symptom headache, has_symptom fatigue, and has_symptom skin rash called erythema migrans. If left untreated, infection can spread to joints, the heart, and the nervous system. (DO)